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This paper shows that quantifier scope phenomena can be precisely charac- terized by a semantic representation cons- trained by surhce constituency, if the di- stinction between referent

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Quantifier Scope and Constituency

J o n g C P a r k

C o m p u t e r a n d I n f o r m a t i o n S c i e n c e

U n i v e r s i t y of P e n n s y l v a n i a

200 S o u t h 3 3 r d S t r e e t , P h i l a d e l p h i a , P A 19104-6389, U S A

park@line, cis upenn, edu

A b s t r a c t Traditional approaches to quantifier scope

typically need stipulation to exclude rea-

dings that are unavailable to human under-

standers This paper shows that quantifier

scope phenomena can be precisely charac-

terized by a semantic representation cons-

trained by surhce constituency, if the di-

stinction between referential and quantifi-

cational NPs is properly observed A CCG

implementation is described and compared

to other approaches

1 I n t r o d u c t i o n

It is generally assumed that sentences with multi-

ple quantified NPs are to be interpreted by one or

more unambiguous logical forms in which the scope

of traditional logical quantifiers determines the rea-

ding or readings There are two problems with this

assumption: (a) without further stipulation there is

a tendency to allow too many readings and (b) there

is considerable confusion as to how many readings

should be allowed arising from contamination of the

semantics of many NL quantifiers by referentiality

There are two well-known techniques for redis-

tributing quantifiers in quantification structures:

quantifying-in (Montague, 1974; Cooper, 1983; Kel-

ler, 1988; Carpenter, 1994) and quantifier raising

(May, 1985) The former provides a compositio-

nal way of putting possibly embedded quantifiers

to the scope-taking positions, and the latter utili-

zes a syntactic movement operation at the level of

semantics for quantifier placement There are also

approaches that put more emphasis on utilizing con-

textual information in restricting the generation of

semantic forms by choosing a scope-neutral repre-

sentation augmented with ordering constraints to

capture linguistic judgments (Webber, 1979; Kamp,

1981; Helm, 1983; Poesio, 1991; Reyle, 1993) And

there are computational approaches that screen una-

vailable and/or redundant semantic forms (Hobbs

Shieber, 1987; Moran, 1988; Vestre, 1991) This pa-

per will show that these approaches allow unavaila-

ble readings, and thereby miss an important gene- ralization concerning the readings that actually are available

This paper examines English constructions that allow multiple occurrences of quantified NPs: NP modifications, transitive or ditransitive verbs, that

complements, and coordinate structures Based on

a critical analysis of readings that are available from these data, the claim is that scope phenomena can

be characterized by a combination of syntactic sur- face adjacency and semantic function-argument re- lationship This characterization will draw upon the old distinction between referential and quantificatio- nal NP-semantics (Fodor & Sag, 1982) We choose

to use Combinatory Categorial Grammar to show how surface adjacency affects semantic function- argument relationship, since CCG has the flexibility

of composing almost any pair of adjacent constitu- ents with a precise notion of syntactic grammatica- lity (Steedman, 1990; 1993) z

The rest of the paper is organized as follows First,

we discuss in §2 how traditional techniques address availability of readings and note some residual pro- blems Then we give a brief analysis of available readings (§3), a generalization of the analysis (§4), and finally describe a computational implementation

in Prolog (~5)

2 T r a d i t i o n a l A p p r o a c h e s All three paradigms of grammar formalisms intro- duced earlier share similar linguistic judgments for their grammaticality analyses This section exami- nes quantifying-in to show (a) that quantifying-

in is a powerful device that allows referential NP- interpretations and (b) that quantifying-in is not suf- ficiently restricted to account for the available rea- dings for quantificational NP-interpretations Quantifying-in is a technique originally introdu- ced to produce appropriate semantic forms for de

re interpretations of NPs inside opaque operators

1 For instance, the result would transfer to Synchro- nous "I~ee Adjoining Grammar (Shieber & Schabes, 1990) without much change

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(Montague, 1974) For example, (a) below has two

readings, de re and de dicto, depending on the rela-

tivity of the existence of such an individual They

are roughly interpretable as (b) and (@2

(1) (a) John believes that a Republican will win

(b) 3r.repub(r) A bel(john, u i l l ( u i n ( r ) ) )

(C) bel(john, 3r.repub(r) A uill(uin(r)))

(b) has a binder 3 that is quaati.fving a variable r

inside an opaque operator b e l , hence the name for

the technique (c) does not have such an interven-

ing operator Although it is beyond the scope of the

present paper to discuss further details of intensio-

nality, it is clear that de re interpretations of NPs

are strongly related to referential NP-semantics, in

the sense that the de re reading of (a) is about a

referred individual and not about an arbitrary such

individual Quantifying-in is designed to make any

(possibly embedded) NP take the matrix scope, by

leaving a scoped variable in the argument position

of the original NP This would be acceptable for re-

ferential NP-semantics

Montague also proposed to capture purely exten-

sional scope ambiguities using quantifying-in For

example, wide scope reading of a w o m a n in (a) below

is accounted for by quantifying-in (with a meaning

postulate), patterned after one for (b)

(2) (a) Every man loves a woman

(b) Every man seeks a white unicorn

His suggestion is adopted with various subsequent

revisions cited earlier Since any NP, referential or

quantificational, requires quantifying-in to outscope

another, quantifying-in consequently confounds re-

ferential and quantificational NP-semantics This

causes a problem when there is a distributional dif-

ference between referential NPs and non-referential

NPs, as Fodor & Sag (1982) have argued, a view

which has been followed by the approaches to dy-

namic interpretation of indefinite NPs cited earlier

It seems hard to reconcile quantifying-in with these

observations

3 A v a i l a b i l i t y o f R e a d i n g s

This section proposes a way of sharpening our intui-

tion on available readings and re-examines traditio-

nal linguistic judgments on grammatical readings

While there are undoubted differences in degree

of availability among readings dependent upon se-

mantics or discourse preference (Bunt, 1985; Moran,

1988), we will focus on all-or-none structural possi-

bilities afforded by competence grammar 3

2In this simplistic notation, we gloss over tense ana-

lysis, among others

3Moran's preference-based algorithm treats certain

readings as "highly unpreferred," effectively making

them structurally unavailable, from those possible sco-

Consider the following unambiguous quantifica- tion structure in a generalized quantifier format (hereafter oq, Barwise & Cooper, 1981), where

q u a n t i f i e r outscopes any quantifiers that may oc-

cur in either r e s t r i c t i o n or body

(3) q u a n t i f i e r ( v a r i a b l e , r e s t r i c t i o n , body) Logical forms as notated this way make explicit the functional dependency between the denotations of two ordered quantificational NPs For example~ con- sider (4) (a) (Partee, 1975) (b) shows one way of representing it in a GQ format

(4) (a) Three Frenchmen visited five Russians (b) t h r e e ( f , frenchmen(f), f i v e ( r ,

russians (r), v i s i t e d ( f , r) ) )

We can always argue, by enriching the notation, that (4) (b) represents at least four different readings, de- pending on the particular sense of each involved NP, i.e., group- vs individual-denoting In every such reading, however, the truth of (4) (b) depends upon finding appropriate individuals (or the group) for f such that each of those individuals (or the group itself) gets associated with appropriate individuals (or a group of individuals) for r via the relation

v i s i l ; e d 4 Notice that there is always a f u n c t i o n a l

d e p e n d e n c y of individuals denoted by r upon indi- viduals denoted by f We claim that this explicit functional dependency can be utilized to test availa- bility of readings 5

First, consider the following sentences without coordination

(5) (a) Two representatives of three companies

saw most samples

(b) Every dealer shows most customers at most three cars

(c) Most boys think that every man d a n c e d with two women

(a) has three quantifiers, and there are 6 different ways of ordering them Hobbs & Shieber (1987) show that among these, the reading in which two re-

p r e s e n t a t i v e s outscopes m o s t s a m p l e s which in turn outscopes three c o m p a n i e s is not available from the sentence They attribute the reason to the logical structure of English as in (3), as it is considered unable to afford an unbound variable, a constraint known as the unbound variable constraint (uvc) 6

We should note, however, that there is one reading pings generated by a scheme similar to Hobbs & Shieber (1887) We clash that competence grammax makes even fewer readings available in the first place

4Without losing generality, therefore, we will consider only individual-denoting NPs in this paper

SSingular NPs such as a company are not helpful to this task since their denotations do not involve multi- ple individuals which explicitly induce this functional dependency

eThe reading would be represented as follows, which has the first occurrence of the variable c left unbound

2 0 6

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among the remaining five t h a t the u v c allows which

in fact does not appear to be available This is the

one in which three companies outscopes m o s t samp-

les which in turn outscopes two representatives (cf

Horn (1972), Fodor (1982)) 7 This suggests t h a t

the u v c m a y not be the only principle under which

Hobbs & Shieber's reading is excluded, s T h e other

four readings of (a) are self-evidently available If

we generalize over available readings, they are only

those t h a t have no quantifiers which intercalate over

NP boundaries 9

(5) (b) has three quantifiers too, b u t unlike (5)

(a), all the six ways of ordering the quantifiers are

available (5) (c) has only four available readings,

where m o s t boys does not intercalate every m a n and

t w o w o m e n 1°

Consider now sentences including coordination

(6) (a) Every girl admired, but most boys dete-

sted, one of the saxophonists

(b) Most boys think t h a t every m a n danced

with, b u t doubt t h a t a few boys talked to,

more t h a n two women

As Geach (1970) pointed out, (a) has only two gram-

matical readings, though it has three quantifiers In

reading 1, the same saxophonist was admired and

detested at the same time In reading 2, every girl

admired an arbitrary saxophonist and most boys

also detested an arbitrary saxophonist In particu-

lar, missing readings include the one in which every

girl admired the same saxophonist and most boys

detested the same but another saxophonist (6) (b)

t h r e e ( c , comp(c), s a g ( r , s ) ) ) )

7To paraphrase this impossible reading, it is true of a

situation under which there were three companies such

that there were four samples for each such company such

that each such sample was seen by two representatives of

that company Crucially, samples seen by representatives

of different companies were not necessarily the same

SThis should not be taken as denying the reality of the

uvc itself For example, as one of the referees pointed

out, the uvc is required to explain why, in (a) below,

every professor must outscope a friend so as to bind the

pronoun his

(a) Most students talked to a friend of every pro-

fessor about his work

9One can replace most samples with other complex

NP such as most samples of at least five products to see

this Certain sentences that apparently escape this ge-

nerafization will be discussed in the next section

1°To see why they are available, it is enough to see

that (a) and (b) below have two readings each

(a) 3ohn thinks that every man danced with two

women

(b) Most boys think that Bill danced with two

women

also has only two g r a m m a t i c a l readings In one,

m o s t boys outscopes every m a n and a f e w boys which together outscope more than two w o m e n In the other, more than two w o m e n outscopes every m a n

and a f e w boys, which together outscope m o s t boys

4 A n A c c o u n t o f A v a i l a b i l i t y This section proposes a generalization at the level of semantics for the p h e n o m e n a described earlier and considers its apparent counterexamples

Consider a language £ for natural language se- mantics t h a t explicitly represents function-argument relationships (Jackendoff, 1972) Suppose t h a t in £: the semantic form of a quantified N P is a syntactic argument of the semantic form of a verb or a pre- position (7) through (10) below show well-formed expressions in £.11

(7) v i s i t l d ( f i v e ( r u l s i i m ) , t h r s e ( f r e n c l u i i n ) )

(8) saw(most (sanp) ,of (thres(cmap) ,two(rap))) (9) show (three(car) ,most (cstmr), every(dlr)) (10) think(Adlmced(two(woman) , e v e r y ( n a n ) ) , most (boy))

For instance, o f has two arguments three(comp)

and t w o ( r e p ) , and show has three arguments /: gives rise to a natural generalization of available readings as summarized below 12

(11) For a function with n arguments, there are n! ways of successively providing all the ar- guments to the function

This generalization captures the earlier observations about availability of readings (7), for (4) (a), has two (2!) readings, as v i a i t e d has two arguments (8) is an abstraction for four (2!x2!) readings, as

b o t h o f and maw have two arguments each (9) is an abstraction for six (3!) readings, as show has three arguments Likewise, (10) is an abstraction for four readings

Coordination gives an interesting constraint on availability of readings Geach's observation that (6) (a) has two readings suggests t h a t the scope of the object must be determined before it reduces with the coordinate fragment Suppose t h a t the non- standard constituent for one of the conjuncts in (6) (a) has a semantic representation shown below (12) ~z a d n i r e d ( z , s v e r y ( g i r l ) )

Geach's observation implies that (12) is ambiguous,

so that every(girl) can still take wide (or narrow) scope with respect to the u n k n o w n argument A 11The up-operator ^ in (10) takes a term of type t to

a term of type e, but a further description of £ is not relevant to the present discussion

1 2 N a n (1991)'s work is based on a related observation, though he does not make use of the distinction between referential and quantificational NP-semantics

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theory of C C G will be described in the next sec-

tion to show h o w to derive scoped logical forms for

available readings only

But first we must consider some apparent coun-

terexamples to the generalization,

(13) (a) Three hunters shot at five tigers

(b) Every representative of a company saw

most samples

The obvious reading for (a) is called conjunctive or

cumulative (Partee, 1975; Webber 1979) In this

reading, there are three hunters and five tigers such

that shooting events happened between the two par-

ties Here, arguments are not presented in succes-

sion to their function, contrary to the present gene-

ralization Notice, however, that the reading must

have two (or more) referential NPs (Higginbotham,

1987) 13 The question is whether our theory should

predict this possibility as well For a precise notion

of availability, we claim that we must appeal to the

distinction between referential and quantificational

NP-semantics, since almost any referential NP can

have the appearance of taking the matrix scope, wi-

thout affecting the rest of scope phenomena A re-

lated example is (b), where in one reading a referen-

tial NP a company arguably outscopes most samples

which in turn outscopes every representative (Hobbs

& Shieber, 1987) As we have pointed out earlier,

the reading does not generalize to quantified NPs in

general

(14) (a) Some student will investigate two dia-

lects of every language

(b) Some student will investigate two dia-

lects of, and collect all interesting examp-

les of coordination in, every language

(c) * Two representative of at least three

companies touched, but of few universi-

ties saw, most samples

(a) has a reading in which every language outscopes

some student which in turn outscopes two dialects

(May, 1985) In a sense, this has intercalating NP

quantifiers, an apparent problem to our generaliza-

tion However, the grammaticality of (b) opens up

the possibility that the two conjuncts can be repre-

sented grammatically as functions of arity two, si-

milar to normal transitive verbs Notice that the

generalization is not at work for the fragment of at

least three companies touched in (c), since the con-

junct is syntactically ungrammatical At the end of

next section, we show how these finer distinctions

are made under the CCG framework (See discussion

of Figure 5)

IZFor example, (a) below lacks such a reading

(a) Several men danced with few women

5 A C C G I m p l e m e n t a t i o n

This section describes a CCG approach to deriving scoped logical forms so that they range over only grammatical readings

We will not discuss details of how CCG charac- terizes natural language syntactically, and refer the interested reader to Steedman (1993) CCGs make use of a limited set of combinators, type raising (T), function composition (B), and function substitution (S), with directionality of combination for syntac- tic grammaticality For the examples in this pa- per, we only need type raising and function composi- tion, along with function application The following shows rules of derivation that we use Each rule is associated with a label, such as > or <B etc, shown

at the end

(15) (a) x / v ~ => x (>) (b) Y x\~ => x (<)

(c) x / v Y/Z => x / z (>a) (d) Y\z x\Y ffi> x \ z (<e) (e) np => T/(T\np) (>T) (f) np => T\(T/np) (<T)

The mapping from syntax to semantics is usually defined in two different ways One is to use ele- mentary categories, such as np or s, in encoding both syntactic types and logical forms (Jowsey, 1990; Steedman, 1990; Park, 1992) The other is to asso- ciate the entire lexical category with a higher-order expression (Kulick, 1995) In this paper, we take the former alternative to describe a first-order rendering

of CCG

Some lexical entries for every are shown below (16) ( s : q - e v e r y (X, N, S ) / ( s : S \ n p : I ) ) / n : X ' N

(17) (s : S/(a : Sknp: s-every(1) ) )/n:W The information ( s / ( s \ n p ) ) / n encodes the syntac- tic fact that every is a constituent which, when

a constituent of category n is provided on its right, returns a constituent of category s / ( s \ n p )

q - e v e r y ( X , l i , S ) is a term for scoped logical forms

We are using different lexical items, for instance

q - e v e r y and e - e v e r y for every, in order to signify their semantic differences 14 These lexical entries are just two instances of a general schema for type- raised categories of quantifiers shown below, where

T is an arbitrary category

(18) (T/(T\np))/na~d (T\(T/np))/n And the semantic part of (16) and (17) is first-order encoding of (19) (a) and (b), respectively 15

14q-every represents every as a quantifier, and

s - e v e r y , as a set denoting property We will

use s-every(l^man(X)) and its ~-reduced equivalent s-every(man) interchangeably

1as-quantifier(noun) denotes an arbitrary set N of individuals d such that d has the property noun and that the cardinality of N is determined by q u a n t i f i e r (and

2 0 8

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(19) (a) ~n.AP.Vz E s-every(n).P(=)

(b)

(a) encodes wide scope type raising and (b), narrow

With standard entries for verbs as in (20), logical

f o r m s such as (21) and (22) are po ible

(20) saw :- (s:sav(I,Y)\np:X)/np:¥

(21) q-two (X, rep (X), aaw(X, s - f ottr (samp)) )

(22) q-two(X,rep(X) ,q-four(Y,samp(Y),aaw(][,¥)))

Figure 1 shows different ways of deriving

scoped logical forms In (a), n : I ' ! unifies with

n : X ' g i r l ( X ) , so that Ii gets the value g i r l ( X )

This value of !1 is transferred to the expression

s : e v o r y ( X , l i , S ) by partial execution (Pereira

Shieber, 1987; Steedman, 1990; Park, 1992) (a)

shows a derivation for a reading in which object NP

takes wide scope and (b) shows a derivation for a rea-

ding in which subject NP takes wide scope There

are also other derivations

Figure 2 shows logical forms that can be derived in

the present framework from Geach's sentence No-

tice that the conjunction forces subject NP to be first

composed with the verb, so that subject NP must be

type-raised and be combined with the semantics of

the transitive verb As noted earlier, the two catego-

ries for the object still make both scope possibilities

available, as desired The following category is used

for but

(23) ((s : and(P ,1~)/np:][)\ (s:P/np:][))/(s :Q/np :][)

Readings that involve intercalating quantifiers, such

as the one where every girl outscopes one sazopho-

nist, which in turn outscopes most bogs, are correctly

excluded

Figure 3 shows two different derivations of logi-

cal forms for the complex NP two representatives of

three companies (a) shows a derivation for a rea-

ding in which the modifying NP takes wide scope

and (b) shows the other case In combination with

derivations involving transitive verbs with subject

and object NPs, such as ones in Figure 1, this cor-

rectly accounts for four grammatical readings for (5)

(a) 16

Figure 4 shows a derivation for a reading, among

six, in which most customers outscopes every dealer

which in turn outscopes three cars Some of these

readings become unavailable when the sentence con-

tains coordinate structure, such as one below

(24) Every dealer shows most customers (at most)

three cars but most mechanics every car

noun) We conjecture that this can also be made to cap-

ture several related NP-semantics, such as collective NP-

semantics and/or referential NP-semantics, though we

can not discuss further details here

lSAs we can see in Figure 3 (a) (b), there m no

way quantifiers inside $ can be placed between the two

quantifiers two & three, correctly excluding the other

two readings

In particular, (24) does not have those two readings

in which every dealer intercalates most customers and three cars This is exactly predicted by the pre-

sent CCG framework, extending Geach's observa- tion regarding (6) (a), since the coordination forces

the two NPs, most customers and three cars, to be

composed first (Dowty, 1988; Steedman 1990; Park 1992) (25) through (27) show one such derivation,

which results in readings where three cars outscopes most customers but every dealer must take either wide or narrow scope with respect to both most cu- stomers and three cars

(25) -oat cuato.ers

(26)

(2T)

((s:q-most(Z,catm'(g),S)~p:g)/np:Y)

\(((s:S\np:X)/np:T)/np:Z)

three cars ( e : q - t h r e e ( Y , c a r ( Y ) , S ) \ n p : l )

\((s:$\np:X)/n]p:f)

a o | t custoaera three cars

<B ( s : q - t h r e e ( ¥ , c a r ( Y ) , q - t t o s t ( Z , c a t m r ( Z ) , S ) )

\np:X)\(((e:S\np:X)/np:T)/np:g) Figure 5 shows the relevant derivation for the frag-

ment investigate two dialects of discussed at end of

previous section It is a conjoinable constituent, but since there is no way of using type-raised category

for two for a successful derivation, two dialects can

not outscope any other NPs, such as subject NP or the modifying NP (Steedman, 1992) This correctly accounts for our intuition that (14) (a) has an ap- parently intercalating reading and that (14) (b) has only two readings However, there is no similar deri-

vation for the fragment of three companies touched,

as shown below

<

n\n (with T =' n\n)

6 C o n c l u d i n g R e m a r k s

We have shown that the range of grammatical rea- dings allowed by sentences with multiple quantified NPs can be characterized by abstraction at function- argument structure constrained by syntactic adja- cency This result is in principle available to other paradigms that invoke operations like QR at LF or type-lifting, which are essentially equivalent to ab- straction The advantage of CCG's very free notion

Trang 6

(a) every girl admired one saxophonist

s : q - e v e r y ( X , l S ) n:X'girl(X) (s:adaired(X.Y)~np:X) s:q-one(Y,sax(Y),S)\(s:S/np:Y) / ( s : S \ n p : X ) / n : X ' i /np:¥

s : q - e v e r y ( X , g i r l ( X ) , S ) / ( s : S \ n p : X )

>B

=:q-every(X.girl(X).adaired(X,Y))/np:Y

(b)

s:q-one(Y,sax(Y).q-every(X,girl(X,adaired(X.Y))))

s : q - e v e r y ( X g i r l ( X ) S ) / ( s : S \ n p : X ) (s:adaired(X.Y)~np:l)

/np:Y s:q-every(X,girl(X).adaired(X,Y))/np:Y

one saxophonist

s : S \ ( s : S / n p : s - o n e ( s a x ) )

s : q - e v e r y ( X g i r l ( X ) a d a i r e d ( X s - o n e ( s a x ) ) )

Figure 1: Every girl admired one sazophonist: Two sample derivations

s : q - e v e r y ( X , g i r l ( l ) a d a i r e d ( l Y ) ) / n p : Y > s : S \ ( s : S / n p : s - o n e ( s a x ) )

<

s : a n d ( q - e v e r y ( X , g i r l ( 1 ) , ~ l ~ - ~ l ( l , Y ) ) , q - m o s t ( l , b o y ( 1 ) , d e t e s t e d ( X , Y ) ) ) / n p : Y

(b)

•:and(q-every(x••irl(•)•ad•ired(••s-•ne(•ax)))•q-•••t(X•b•y(X)•detested(••s-•ne(sax))))

every g i r l admired but most boys d e t e s t e d one saxophonist

s : a d a i r e d ( s - e v e r y ( g i r l ) , Y ) / n p : Y ~ s:q-one(Y,sax(Y),S)\(s:S/np:¥) s:and(admired(s-every(girl),Y),detested(s-most(boy),W))/np:Y

s:q-one(Y,sax(Y),and(adaired(s-every(girl),Y),detested(s-most(boy),Y)))

Figure 2: Every girl admire~ but most boys detested, one sazophonist: Two sample derivations

( s : q - t e o ( X | S )

/ ( s : S ~ n p : l ) ) / n : l ' l

n:X'and(rep(X),of(X.Y))/np:Y

>B ( s : q - t v o ( l , a n d ( r e p ( l ) , o f ( X , Y ) ) , S ) / ( s : S \ n p : X ) ) / n p : ¥

( s : q - t h r e e ( C c o m p ( C ) , S 2 ) / ( s : S t \ n p : l ) )

\ ( ( s : S 2 / ( s : S l ~ n p : l ) ) / n p : C )

(b)

a:q-three(C,comp(C).q-two(X.and(rep(X),of(X.C)),S))/(s:S\np:X) two r e p r e s e n t a t i v e s of t h r e e companies

(s:q-twoCX,l,s) n:X'and(rep(i).of(X,Y))/np:Y ( s : S 2 / ( s : S t \ n p : X ) )

/ ( s : S \ n p : i ) ) / n : g ' N \ ( ( s : S 2 / ( s : S t \ n p : X ) ) / n p : s - t h r e e ( c o a p ) )

>B (s:q-two(X.and(rep(X),of(X,Y)),S)/(s:S\np:X))/np:Y

s :q-tgo (X, and(rep(l) ,of (X,s-three (¢oap))) ,S)/(s:S\np:I)

Figure 3: two representatives o/three companies: Two sample derivations

210

Trang 7

e v e r y d e a l e r shows h o s t c u s t o n e r s

s:q-every(X,dlr(X),S) (s:ehow(X,Y,g)\np:I) (s:q-nost(Y,cstnr(Y),S)

>B

s:q-every(X,dlr(X),shog(X,Y,g)/np:Z/np:Y

s:q-nost(Y,cstaw(Y),q-every(X,dlr(X),show(X,Y,Z)))/np:g

three cars

s : S \ ( s : S

/ n p : s - t h r e e ( c a r ) )

s:q-nost(Y,cstnr(Y),q-every(X,dlr(X),show(X,Y,s-three(car))))

Figure 4: Every dealer shows most customers three cars: One sample derivation

(s:investigate(X,g)~ap:X)

/np:Y

np:s-two(l) n : l t / ( n : i l ( n : Y ' t n d ( l , o f ( l , Z ) ) ~ n : I 1 )

/ n : i \ n : Y ' d i a l e c t ( Y ) ) /np:g

~ B n: Y'and(dialect (g) ,of (g,z))/np:Z

>B

rip: s - t w o ( Y ' a n d ( d i a l e c t ( ¥ ) , o f ( Y , Z ) ) ) / r i p : Z

~ B (s:investigate(g,s-tuo(Y'and(dialect(Y),of(Y,Z)))\np:X)/np:Z

Figure 5: investigate two dialects of One derivation

of surface structure is that it ties abstraction or the

equivalent as closely as possible to derivation Ap-

parent counterexamples to the generalization can be

explained by the well-known distinction between re-

ferential and quantificational NP-semantics An im-

plementation of the theory for an English fragment

has been written in Prolog, simulating the 2nd order

properties

There is a question of how the non-standard sur-

face structures of CCG are compatible with well-

known conditions on binding and control (including

crossover) These conditions are typically stated on

standard syntactic dominance relations, but these

relations are no longer uniquely derivable once CCG

allows non-standard surface structures We can

show, however, that by making use of the obliquen-

ess hierarchy (of Jackendoff (1972) and much sub-

sequent work) at the level of LF, rather than sur-

face structure, it is possible to state such conditions

(Steedman, 1993)

A c k n o w l e d g e m e n t s

Special thanks to Mark Steedman Thanks also to

Janet Fodor, Beryl Hoffman, Aravind Joshi, Nobo

Komagata, Anthony Kroch, Michael Niv, Charles L

Ortiz, Jinah Park, Scott Prevost, Matthew Stone,

Bonnie Webber, and Michael White for their help

and criticism at various stages of the presented

idea Thanks are also due to the anonymous referees

who made valuable suggestions to clarify the paper

Standard disclaimers apply The work is supported

in part by NSF grant nos IRI91-17110, and CISE

IIP, CDA 88-22719, DARPA grant no N660001-94- C-6043, and ARO grant no DAAH04-94-G0426

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